10 Things I Didn’t Know About Aquaculture

Is aquaculture sustainable? Depends on what’s being raised, how and where it’s being produced, and whom you ask. With over 500 species being farmed all over the world, it’s difficult to generalize. But here are some of the many things I learned from listening to experts Craig Tucker (Research Leader, Agriculture Research Service, USDA), Jesse Trushenski (Assistant Professor, Center for Fisheries, Aquaculture, and Aquatic Sciences), and Carole Engle (Aquaculture Economist, University of Arkansas at Pine Bluff), speak on a March 16 panel at the 2014 Seafood Expo North America.

Aquaculture is rapidly evolving. Over the last 10-15 years, aquaculture has become more efficient. There’s also been a 50 percent reduction in waste production in the last 10 years, thanks to better solids capture, better waste treatment, and more efficient feeds.

About 75% of the energy used in aquaculture goes into producing and transporting the feed. But the amount of energy use varies by species, from very low use to raise carp to very high use (equivalent to raising cattle in feedlots) to produce shrimp in ponds.

Most of the fish raised around the world are relatively low in energy use. Aquaculture uses less energy than capture fishery, but raising cattle, wine and poultry requires much more energy than either.

Aquaculture uses less land to produce food than other forms of agriculture, but it varies by species. For example, raising salmon and trout requires relatively little land, because they consume more fish products (and less grain) in their feed.

The amount of water used for aquaculture also varies. Water use at the facility, as well as water used to produce the feed, can be pretty high. Pond aquaculture uses the most water of any type of agriculture—even more than raising cattle.

Although many people are concerned about the high feed conversion ratio—how much food an animal must consume in order to produce food—the ratio to produce fish averages 1 to 1.5 to 1, compared to 2:1 for poultry, 3:1 for swine, and 8:1 for beef.

Aquaculture consumes about 74% of the fish oil supply and the price of fish meal and fish oil are increasing. Eventually, it may be hard to get enough supply at any price.

US farmed fish is NOT full of antibiotics. FDA drug approval for aquaculture is more rigorous than for other animals. Antibiotics are not used as growth promoters in US aquaculture.

Over 94 percent of US aquaculture is run by small farms or small businesses.

Much of US aquaculture occurs in impoverished rural areas. 1 fish farm job equals 4.3 additional jobs in the US economy.